Railway traffic controlling apparatus



May 16, 193.3. A, T, JOHNSTON 1,908,761

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed May 9, 1931 INVENTOR.

E. 7 TO h I? 5 t 5 r7 N4 ATTORNEY.

Patented May 16, 1933 UNITED STATES ALLAN T. JOHNSTON, OF MOUNT LEBANON,

PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SW'ISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed May 9,

My invention relates to railway traflio controlling apparatus, and has for an object the protection of such apparatus from excessive currents that might be injurious.

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view, showing one form of apparatus embodying my invention.

Referring to the drawing, the reference character A designates a railway switch which is actuated by an electric motor M having an armature 1 and a field 2. Operatively connected with the switch is a cut-out controller MC comprising a contact arm and contacts 3 and 4. Contact 503 is closed at all times except when the switch occupies its extreme reverse position, and contact 504 is closed at all times except when the switch occupies its extreme normal position.

The motor M is controlled in part by a circuit controller designated by the reference character P, and which is, in turn, controlled by a pole-changer L which may be incorporated in a switch lever of an interlocking machine. The circuit controller P comprises an electromagnet 9, made up of two windings 9 and 9 and a polarized winding 10 which is preferably provided with a permanently magnetized core 11. Pivotally attached to the core 11 is an armature 12 which is therefore polarized by flux from the permanent magnet core 11 at such times as winding 10 is not carrying current. It follows that when the electromagnet 9 is supplied with current of one polarity, the armature 12 will be swung in a clockwise direction, but that when current of the opposite polarity is supplied to electromagnet 9, the armature will be swung in the opposite direction. The armature 12 controls three pivoted contact yokes 13, 14 and 15 through suitable linkage in such manner that the yokes occupy their right-hand positions when the armature is swung to the left, and vice versa.

The reference character B designates a neutral magnet which controls a pivoted 1931. Serial No. 536,224.

armature 17, the lower end of which projects into the path of movement of a portion of armature 12 to prevent reversal of the armature 12 when the neutral magnet B is deenergized. Pivotally attached to the armature 17 is a link 19 provided with a slot 43 which at times engages a pin 42 in a rocker arm 70 which carries a contact finger 20. When magnet B is deenergized, the link 19 moves the rocker arm 70 against the bias exerted by spring 44 into a position in which the contact finger 20 connects wire 33 with wire 34. When neutral magnet B is energized, however, the spring 44 urges the rocker arm 70 into a position wherein the contact between wires 33 and 34 is interrupted.

The apparatus thus far referred to is illustrated and described in United States Letters Patent No. 1,722,364, granted to Henry S. Young, on the 30th day of July, 1929, for Railway traffic controlling apparatus.

The reference character R designates an automatic thermal overload circuit breaker. The circuit breaker R comprises a tripping core 25 on which is a winding 23, and a holding core 24 on which are windings 28 and 29. Winding 23 is connected in series with the motor circuit so that it carries the entire motor operating current. findings 28 and 29 are energized from the potential across the thermal relay windings 16 and 18, respectively. The circuit for winding 28 is from one terminal of thermal relay winding 16, wire 31, winding 28, wire 51, contact 56-46, and wire 47 to the other terminal of thermal relay winding 16. The circuit for winding 29 is from one terminal of thermal relay winding 18, wire 36, Winding 29, wire 39, contact 3837, and wire 48 to the other terminal of thermal relay winding 18. Armature 21 of the circuit breaker is normally held open by rod 27 due to the compression of spring 22 and the attraction of armature 26. When armature 21 is attracted, detent 57 will be raised, raising link 19 and thus disengaging slot 43 from pin 42 and opening contact 3334. The parts of the circuit breaker R are so designed that as long as either of the two windings on core 24 is fully energized, the maximum amount of current that can be drawn by the switch motor, passing through coil 23, will not attract the armature 21 of coil 23 against the pull of the armature 26 by either coil 28 or 29.

As shown in the drawing, the switch A. occupies its normal position; the neutral magnet B is deenergized, thereby locking armature 12 of circuit controller P in its left-hand position; and the pole-changer L on the switch lever occupies its normal position.

When the switch is to be moved to the re verse position, pole-changer L will be reversed, thereby reversing circuit controller P. The motor circuit will then be from terminal BH of a source of current, through wire 7 wire 18, winding 23, wire 33, contact 20, wire 34, wire 30, yoke 13, flexible connector 54, wire 35, armature 1, wire 41, flexible connector 53, yoke 14, wire 45, thermal relay winding 18, contact 3, contact arm 50, and field 2 to terminal CH of the same source of current. The holding coil 29 associated with this circuit is energized by the voltage drop across thermal relay winding 18.

When the switch A moves to the normal position from the reverse position, the motor circuit is from terminal BH, through wire 7 wire 18, winding 23, wire 33, con tact 20, wire 34, wire 32, yoke 14, flexible connector 53, wire 41, armature 1, Wire 35, flexible connector 54, yoke 13, wire 40, winding 16, contact 4, controller arm 50, and field 2 to terminal CH. The holding coil associated with this circuit is winding 28, and it is energized by the voltage drop across thermal relay winding 16.

In describing the operation of the apparatus, I will. assume it is desired to move the switch to the reverse position. Pole-changer L will be reversed, so that current will flow through neutral magnet B, thus attracting armature 17 and closing suitable contacts so that the polarity of controller P will be reversed, and armature 12 will move to the right in which position it will be locked and armature 17 will again be released. The movement of armature 12 to the right will move yokes 13, 14 and 15 to the left, completing the motor circuit when armature 17 is released, thereby closing contact 33-34 through contact 20, and the switch will move to the reverse position. If an obstruction occurs in switch A while moving to the reverse position, the motor current will rise above the value necessary to operate thermal relay T and contact 37-38 will open, opening the holding coil circuit. With the holding coil circuit open, armature 26 is not attracted, and armature 21 will be pulled down by the attraction of energized coil 23.

Detent 57 will then raise link 19, disengaging slot 43 from pin 42, and arm will move to the right due to the bias exerted by compressed spring 44. Contact 33--34 will therefore be opened, 0 ening the motor circuit. The circuit brea er, once having been tripped, will not reset until the controller P has moved to the opposite position. Resetting the circuit breaker is accomplished by reversing pole-changer L, thus energizing neutral magnet B and attracting armature 17, and moving link 19 so that slot 43 engages pin 42. Armature 17 will close suitable contacts which ener ize controller P, reversing its polarity, ant armature 12 will move to the left, moving yokes 13, 14 and 15 to the right, and the motor circuit will then be completed for reverse rotation when armature 11 is released closing contact 3334 through contact 20. When the switch returns to the original position, the operalion may be repeated as first described.

In a similar manner, if the switch is to be moved from the reverse position to the normal position, the pole-changer L is moved to the position shown on the drawing, thus energizing neutral magnet B and attracting armature 17. Armature 17 will close suitable contacts which energize controller P so that armature 12 will move to the left, and yokes 13, 14 and 15 will move to the right, completing the motor circuit when armature 17 is released to close contact 33-34 through contact 20. The switch will then move to the normal position. If an obstruction occurs in switch A while it is moving to the normal position, the motor current will rise above the value necessary to operate thermal relay T, and contact 46-56 will open, opening the holding coil circuit. With the holding coil circuit open, armature 26 will not be attracted, and armature 21 will be pulled down by the attraction of energized coil 23. Detent 57 will then raise link 19, disengaging slot 43 from pin 42, and arm 70 will move to the right due to the bias exerted by compressed spring 44. Contact 3334 will then be opened, opening the motor circuit. The circuit breaker being tripped will not reset until controller P has moved to the opposite position. Resetting the controller is accomplished by reversing pole-changer L, thus energizing neutral magnet B and attracting armature 17 and moving link 19 so that slot 43 engages pin 42. Armature 17 will close suitable contacts which energize controller P, reversing its polarity, and armature 12 will move to the right, moving yokes 13, 14 and 15 to the left, and the motor circuit will be completed when armature l7 is released to close contact 33-34 through contact 20. When switch A returns to the original position, the operation may be repeated as before described.

One advantage of apparatus embodying my invention is that it is possible to restore the switch to its last operated position iinmediately and to attempt to operate the switch again in the direction in which it failed as soon as the thermal relay for that direction has cooled so as to complete the holding coil circuit. A further advantag that the holding coil circuit is normally doenergized, being active only when the switcl. motor is being operated.

Although I have herein shown and described only one iorm of apparatus embody ing my invention, it is unoerstood that various changes and modifications may be made therein within the scope of the appended claims without departing From the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, an electric motor, an operating circuit for said motor, a thermal relay having a heating winding included in said motor circuit and a contact, a circu t breaker for controlling the supply of current to said motor having a first and a second magnetizable core magnetically independent of each other, a winding on said first core included in said motor circuit, arr a winding on said second core connected in parallel with said heating Winding and controlled by said contact.

2. In combination, an electric motor, an operating circuit for said motor, a thermal relay having a heating winding included in said motor circuit and a normally closed contact, a circuit breaker for controlling the supply of current to said motor having a first and a second magnetizable core magnetically independent of each other, a winding on said first core included in said motor circuit, and a winding on said second core connected in parallel with said heating winding and including said contact.

3. In combination, an electric motor, an operating circuit for said motor, a thermal relay having a heating winding included in said operating circuit and a contact, a circuit breaker for controlling the supply of current to said motor having a first and a second magnetizable core magnetically independent of each other, an actuating winding on said first core included in said oper ating circuit, means controlled by said actuating winding for tripping said circuit breaker, a holding winding on said second core controlled by said contact, means for energizing said holding winding from the potential drop across said heating winding, and means controlled by said holding wind ing for preventing said circuit breaker from tripping.

4. In combination, an electric motor, a normal and a reverse thermal relay each having a heating winding and a contact, a normal and a reverse operating circuit for said motor including the heatin Winding of said normal and said reverse t ermal relay respectively, a circuit breaker for c0ntrolling the supply of current to said motor having a first and second magnetizable core magnetically independent of each other, an actuating winding on said first core included in both of said operating circuits, means controlled by said actuating winding for tripping said circuit breaker, a first and a second holding winding on said second core controlled by the contact of said normal and said reverse thermal relay respectively, means for energizing said first and said second holding windings from the potential drop across the heating Winding of said normal and said reverse thermal relay respectively, and means controlled by said first or said second holding winding for preventing said circuit breaker from tripping.

5. In combination, an electric motor, an operating circuit for said motor, a thermal relay having a heating winding included in said operating circuit and a contact, a circuit breaker for controlling the supply of current to said motor having a first and a second magnetizable core magnetically inde pendent of each other, an actuating winding on said first core included in said operating circuit, means controlled by said actuating winding for tripping said circuit breaker, means controlled by flux in said second core for preventing said circuit breaker from tripping, other means for supplying fiux to said second core, and means governed by said contact for controlling said other means in accordance with the potential drop across said heating winding.

6. In combination, an electric motor, a normal and a reverse thermal relay each having a heating winding and a normally closed contact, a normal and a reverse operating circuit for said motor including the heating winding of said normal and said reverse thermal relay respectively, a circuit breaker for controlling the supply of current to said motor having a first and second magnetizable core magnetically independent of each other, an actuating winding on said first core included in both of said operating circuits, means controlled by said actuating winding for tripping said circuit breaker, a first and a second holding winding on said second core including the contact of said normal. and said reverse thermal relay respectively, means for energizing said first and said second holding windings from the potential drop across the heating winding o1 said normal and said reverse thermal relay respectively, and means controlled by said first or said second holding Winding for preventing said circuit breaker from tripping.

In testimony whereof I afiix my signature.

ALLAN T. JOHNSTON. 

